Hybrid heart valves

ABSTRACT

A prosthetic heart valve configured to replace a native heart valve and having a support frame configured to be reshaped into an expanded form in order to receive and/or support an expandable prosthetic heart valve therein is disclosed, together with methods of using same. The prosthetic heart valve may be configured to have a generally rigid and/or expansion-resistant configuration when initially implanted to replace a native valve (or other prosthetic heart valve), but to assume a generally expanded form when subjected to an outward force such as that provided by a dilation balloon or other mechanical expander. An inflow stent frame is expandable for anchoring the valve in place, and may have an outflow end that is collapsible to a limited degree for delivery and expandable post-implant to facilitate valve-in-valve (ViV) procedures. The hybrid heart valves eliminate earlier structural bands, which both reduces manufacturing time and facilitates ViV procedures.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/199,748, filed Jun. 30, 2016, now issued as U.S. Pat. No. 10,456,246,which claims the benefit of U.S. Application No. 62/188,465, filed Jul.2, 2015, the entire disclosure of which is incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to a hybrid heart valve for heart valvereplacement, and more particularly to modifications to simplify theconstruction of hybrid heart valves.

BACKGROUND

The heart is a hollow muscular organ having four pumping chambersseparated by four heart valves: aortic, mitral (or bicuspid), tricuspid,and pulmonary. Heart valves are comprised of a dense fibrous ring knownas the annulus, and leaflets or cusps attached to the annulus.

Heart valve disease is a widespread condition in which one or more ofthe valves of the heart fails to function properly. In a traditionalvalve replacement operation, the damaged leaflets are typically excisedand the annulus sculpted to receive a replacement prosthetic valve.

In tissue-type valves, a whole xenograft valve (e.g., porcine) or aplurality of xenograft leaflets (e.g., bovine pericardium) can providefluid occluding surfaces. Synthetic leaflets have been proposed, andthus the term “flexible leaflet valve” refers to both natural andartificial “tissue-type” valves. In a typical tissue-type valve, two ormore flexible leaflets are mounted within a peripheral support structurethat usually includes posts or commissures extending in the outflowdirection to mimic natural fibrous commissures in the native annulus.The metallic or polymeric “support frame,” sometimes called a “wireform”or “stent,” has a plurality (typically three) of large radius cuspssupporting the cusp region of the flexible leaflets (e.g., either awhole xenograft valve or three separate leaflets). The ends of each pairof adjacent cusps converge somewhat asymptotically to form upstandingcommissures that terminate in tips, each extending in the oppositedirection as the arcuate cusps and having a relatively smaller radius.Components of the valve are usually assembled with one or morebiocompatible fabrics (e.g., polyester, for example, Dacron®polyethylene terephthalate (PET)) coverings, and a fabric-covered sewingring is provided on the inflow end of the peripheral support structure.

There is a need for a prosthetic valve that can be surgically implantedin a body channel in a more efficient procedure so as to reduce the timerequired on extracorporeal circulation. One solution especially foraortic valve replacement is provided by the Edwards Intuity® valvesystem available from Edwards Lifesciences of Irvine, Calif. Aspects ofthe Edwards Intuity® valve system are disclosed in U.S. Pat. No.8,641,757 to Pintor, et al. The Edwards Intuity® valve is a hybrid of asurgical valve and a plastically-expandable stent that helps secure thevalve in place in a shorter amount of time.

Despite certain advances in this area, there remains a need for asimplified prosthetic heart valve that facilitates implant andsimplifies manufacturing techniques.

SUMMARY

The application discloses a hybrid prosthetic heart valve (and methodsfor making the same) having a stent frame positioned at the inflow endof the prosthetic heart valve configured to plastically expand into asubstantially flared shape when subjected to a dilation force that is byitself insufficient to cause expansion of the main support structure.The stent frame is positioned upstream or on the inflow end of theentire valve portion. The application also discloses a hybrid prostheticheart valve configured to receive a prosthetic heart valve, such as acatheter-deployed (transcatheter) prosthetic heart valve, therein—e.g.,it is adapted for valve-in-valve (ViV) procedures.

An exemplary hybrid prosthetic heart valve having an inflow end and anoutflow end, and comprises a valve member including a plurality offlexible leaflets configured to ensure one-way blood flow therethrough.A generally tubular expandable inflow stent frame having aradially-expandable inflow end and an outflow end is secured to andprojects from an inflow end of the valve member. The outflow end of thestent frame undulates with peaks and valleys, and the outflow endincludes integrated commissure posts to which the leaflets attach. Theoutflow end of the stent frame has a circumferential structure defininga nominal diameter that enables physiological functioning of the valvemember when implanted. The circumferential structure is radiallyexpandable from the nominal diameter to a larger expanded diameter uponapplication of an outward dilatory force from within the stent framesubstantially larger than forces associated with normal physiologicaluse. And the circumferential structure has limited radiallycompressibility of between about 7-20% of the nominal diameter to reducethe size of the outflow end during delivery of the heart valve.

A further hybrid prosthetic heart valve disclosed herein and adapted forpost-implant expansion has an inflow end and an outflow end with a valvemember and an inflow stent frame. The valve member includes anundulating wireform supporting a plurality of flexible leafletsconfigured to ensure one-way blood flow therethrough. The stent frame isplastically-expandable with a radially-expandable inflow end and anoutflow end secured to an inflow end of the wireform. The stent frameprojects from the inflow end of the wireform and the outflow endundulates with peaks and valleys corresponding to the wireform. Theoutflow end further includes integrated commissure posts to which theleaflets attach, and defines an implant circumference that isnon-compressible in normal physiological use and has a nominal diameter.The stent frame outflow end permits expansion from the nominal diameterto a second diameter larger than the nominal diameter upon applicationof an outward dilatory force from within the outflow end substantiallylarger than forces associated with normal physiological use.

Another hybrid prosthetic heart valve disclosed herein comprises a valvemember including an undulating wireform supporting a plurality offlexible leaflets configured to ensure one-way blood flow therethrough.A plastically-expandable inflow stent frame having a radially-expandableinflow end and an outflow end is secured to an inflow end of thewireform. The stent frame projects from the inflow end of the wireformand the outflow end undulates with peaks and valleys corresponding tothe wireform. The outflow end includes integrated commissure posts towhich the leaflets attach outside of the wireform, and the outflow endcomprises a circumferential structure defining a nominal diameter thatenables functioning of the valve member. The circumferential structureis radially compressible to a smaller contracted diameter to enablecompression of the outflow end during delivery of the heart valve, andradially expandable from the nominal diameter to a larger expandeddiameter upon application of an outward dilatory force from within thestent frame substantially larger than forces associated with normalphysiological use.

Other features and advantages of the present invention will becomeapparent from the following detailed description, taken in conjunctionwith the accompanying drawings that illustrate, by way of example, theprinciples of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an exploded view of an inner structural band subassembly of aprior art prosthetic heart valve, and FIG. 1B shows the band subassemblyhaving been covered with cloth and exploded over a peripheral sealingring;

FIG. 1C shows the cloth-covered band subassembly joined with theperipheral sealing ring also covered in cloth, while FIG. 1D is avertical sectional view through a cusp region thereof;

FIG. 2A is a perspective view of a flexible leaflet subassembly for usein the prior art prosthetic heart valve, and FIG. 2B shows an undulatingwireform used for support thereof;

FIG. 2C is a perspective view of a subassembly of the undulatingwireform covered in fabric, and FIG. 2D is a detailed sectional view ofa cusp portion thereof;

FIG. 2E shows a leaflet and wireform subassembly for prior artprosthetic heart valves;

FIG. 3 is a perspective view of a finished prior art prosthetic heartvalve including the combination of the subassemblies shown in FIGS. 1Cand 2E;

FIGS. 4A and 4B are inflow and outflow perspective views, respectively,of a prosthetic heart valve as in FIG. 3 before coupling with an inflowanchoring skirt to form a hybrid prosthetic heart valve;

FIG. 5 is an exploded assembly view of a portion of a cloth-coveredanchoring skirt for coupling to the heart valve;

FIG. 6 is an exploded assembly view of the portion of the cloth-coveredanchoring skirt shown in FIG. 5 and a lower sealing flange securedthereto to form the inflow anchoring skirt;

FIG. 7A shows the valve member above the cloth-covered anchoring skirtand schematically shows one method of coupling the two elements, whileFIG. 7B illustrates an inner plastically-expandable stent frame of theanchoring skirt and the pattern of coupling sutures passed therethrough;

FIG. 8A is a side view of a hybrid prosthetic heart valve of the presentapplication, while FIG. 8B shows an anchoring skirt therefor with avalve member in phantom, and FIG. 8C is a perspective view of theprosthetic heart valve with portions cutaway to reveal internalstructural leaflet supports;

FIGS. 9A-9C are perspective views of an exemplary anchoring skirt foruse in the hybrid prosthetic heart valve of FIGS. 8A-8C;

FIG. 10A is an exploded perspective view of components of an alternativehybrid prosthetic heart valve, while FIG. 10B shows an exemplary leafletand wireform subassembly and an anchoring skirt and commissure postsubassembly for the hybrid prosthetic heart valve;

FIGS. 10C and 10D show details of separate commissure posts;

FIG. 11 is another exploded perspective view of subassemblies of thealternative hybrid prosthetic heart valve;

FIG. 12 shows the relative positions of the anchoring skirt andcommissure post subassembly and wireform for the alternative hybridprosthetic heart valve, and FIGS. 12A-12D are further detailed viewsthereof;

FIG. 13 is a perspective view of the finished hybrid prosthetic heartvalve;

FIGS. 14A and 14B are perspective views of a hybrid prosthetic heartvalve built using the methods of FIGS. 15-16 ;

FIGS. 15A and 15B show steps for covering an anchoring frame member withcloth in the disclosed method of hybrid valve construction;

FIGS. 16A and 16B show methods of attachment of a suture permeablesealing ring to the anchoring frame member;

FIG. 17 is a perspective view of a separate commissure post, and FIG. 18is the commissure post covered with cloth;

FIGS. 19A and 19B are elevational views of an exemplary integrated framemember of the present application;

FIG. 20 is an alternative commissure post;

FIG. 21 is a tubular legs of fabric used to cover the separatecommissure posts;

FIGS. 22A and 22B are perspective views of a cloth-covered commissurepost secured to an outflow edge of a cloth-covered anchoring framemember;

FIG. 23 illustrates alternative commissure posts, and FIG. 24 shows onealternative commissure post secured to an outflow edge of acloth-covered anchoring frame member;

FIGS. 25A-25D are perspective, elevational, and flat plan views of anexemplary integrated frame member for use in the hybrid prosthetic heartvalves disclosed herein;

FIGS. 26A-26D are several views of an alternative integrated framemember much like that shown in FIGS. 25A-25D but with commissure poststhat are separated from a lower expandable frame;

FIGS. 27A and 27B are perspective and elevational views of a stillfurther integrated frame member of the present application that isnon-collapsible and non-expandable;

FIGS. 28A and 28B are perspective and elevational views of anotherintegrated frame member with separate commissure posts;

FIG. 29 is a perspective view of an alternative integrated frame memberhaving an expandable frame connected to a polymer band that formscommissure posts;

FIGS. 30A and 30B are elevational and perspective views of an exemplaryexpandable frame for use in the frame member of FIG. 29 ; and

FIG. 31 is an elevational view of an integrated frame member similar tothat shown in FIG. 29 with the polymer band overlapping an upper edge ofthe expandable frame.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

The prosthetic heart valves disclosed herein are “hybrid” in that theyinclude a prosthetic valve member with a relatively stable diameter, anda lower expandable frame structure to help in anchoring the valve inplace. Most prior valves have either a whollynon-compressible/non-expandable valve member or a wholly expandableframe structure that incorporates a valve therein. One specificcommercial prosthetic heart valve that is constructed in a hybrid manneris the Edwards Intuity® valve system from Edwards Lifesciences ofIrvine, Calif. The hybrid Edwards Intuity® valve system comprises asurgical non-compressible/non-expandable valve member (e.g., EdwardsMagna Ease® valve) having bioprosthetic (e.g., bovine pericardial)leaflets coupled to a stainless steel expandable frame structure on itsinflow end.

FIGS. 1-7 illustrate a number of steps in the construction of anexemplary hybrid prosthetic heart valve 20.

FIG. 1A is an exploded view of an inner structural band subassembly 40,and FIG. 1B shows the band subassembly having been covered with clothand exploded over a peripheral sealing ring. The inner structural bandsubassembly 40 includes an inner polymer band 42 having three upstandingposts 44 and a scalloped lower ring 46, and an outer more rigid band 48having a scalloped shape to conform to the lower ring 46. The bandsubassembly 40 is formed by positioning the polymer band 42 within therigid band 48 and securing them together with sutures through alignedholes, for example.

FIG. 1B is a perspective view of the assembled band subassembly 40covered in cloth exploded from a sewing ring 68. The two structuralbands 42, 48 are the same heights in the cusp region and encompassed bya fabric cover 64 that is rolled into a peripheral tab 66. As seen inFIG. 1D, the sewing ring 62 comprises an inner suture permeable member68 having a frustoconical form and encompassed by a second fabric cover70. Two fabric covers 64, 70 are sewn together at a lower junction point72 to form the cloth-covered assembly of FIG. 1C, while FIG. 1D showsdetails through a cusp portion thereof.

FIG. 2A is a perspective view of a flexible leaflet subassembly and FIG.2B shows an undulating wireform used for support thereof. FIG. 2C is aperspective view of a cloth-covered wireform subassembly 50, and FIG. 2Dis a detailed sectional view of a cusp portion of the wireform 50showing an inner wire member 52 covered with fabric that defines atubular portion 54 and an outwardly projecting flap 56. The wireform 50defines three upstanding commissure posts 58 and three downwardly convexcusps 60. This is a standard shape for tri-leaflet heart valves andmimics the peripheral edges of the three native aortic leaflets. Theshape of the wireform 50 coincides with the upper edge of the bandsubassembly 40, and defines the outflow edge of the prosthetic valve 20.The wireform subassembly 50 is then joined together with the flexibleleaflet subassembly, as seen in FIG. 2E.

FIG. 3 is a perspective view of a finished valve member including thecombination of the subassemblies shown in FIGS. 1C and 2E.

FIGS. 4A and 4B are inflow and outflow perspective views, respectively,of the surgical heart valve member 24 before coupling with an inflowanchoring skirt to form the hybrid heart valve 20. Although constructiondetails are not shown, three flexible leaflets 74 are secured along theundulating wireform 50 and then to the combination of the bandsubassembly 40 and sewing ring 62 shown in FIG. 1C. In a preferredembodiment, each of the three leaflets includes outwardly projectingtabs that pass through the inverted U-shaped commissure posts 58 andwrap around the cloth-covered commissure posts 75 (see FIG. 1C) of theband subassembly 40. The entire structure at the commissures is coveredwith a secondary fabric to form the valve commissures 35 as seen in FIG.7A.

One feature of the valve member 24 that is considered particularlyimportant is the sewing ring 62 that surrounds the inflow end thereof.As will be seen, the sewing ring 62 is used to attach the anchoringskirt 26 to the valve member 24. Moreover, the sewing ring 62 presentsan outward flange that contacts an atrial side of the annulus, while theanchoring skirt 26 expands and contracts the opposite, ventricular sideof the annulus, therefore securing the heart valve 20 to the annulusfrom both sides. Furthermore, the presence of the sewing ring 62provides an opportunity for the surgeon to use conventional sutures tosecure the heart valve 20 to the annulus as a contingency.

The preferred sewing ring 62 defines a relatively planar upper oroutflow face and an undulating lower face. Cusps of the valve structureabut the sewing ring upper face opposite locations where the lower facedefines peaks. Conversely, the valve commissure posts align withlocations where the sewing ring lower face defines troughs. Theundulating shape of the lower face advantageously matches the anatomicalcontours of the aortic side of the annulus AA, that is, thesupra-annular shelf. The ring 62 preferably comprises a suture-permeablematerial such as rolled synthetic fabric or a silicone inner corecovered by a synthetic fabric. In the latter case, the silicone may bemolded to define the contour of the lower face and the fabric coverconforms thereover.

Now with reference to FIGS. 5 and 6 , assembly of the cloth-coveredanchoring skirt 26 will be described. FIG. 5 is an exploded assemblyview of a portion of a cloth-covered anchoring skirt for coupling to thevalve member, and FIG. 6 is an exploded assembly view of the portion ofthe cloth-covered anchoring skirt shown in FIG. 5 and a lower sealingflange secured thereto to form the inflow anchoring skirt. It shouldfirst be noted that the size of the anchoring skirt 26 will varydepending on the overall size of the heart valve 20. Therefore thefollowing discussion applies to all sizes of valve components, with thedimensions scaled accordingly.

The general function of the anchoring skirt 26 is to provide the meansto attach the prosthetic valve member 24 to the native aortic root. Theanchoring skirt 26 may be a pre-crimped, tapered, 316L stainless steelballoon-expandable stent, desirably covered by a polyester fabric tohelp seal against paravalvular leakage and to promote tissue ingrowthonce implanted within the annulus. The anchoring skirt 26 transitionsbetween the tapered, constricted shape of FIG. 5B to a flared, expandedshape. The anchoring skirt 26 comprises an inner stent frame 80, afabric covering 82, and a band-like lower sealing flange 84. The stentframe 80 assembles within a tubular section of fabric 82, which is thendrawn taut around the stent frame, inside and out, and sewn thereto toform the intermediate cloth-covered frame 88 in FIG. 5 . During thisassembly process, the stent frame 80 is desirably tubular, though laterthe frame will be crimped to a conical shape as see in FIG. 7B forexample. A particular sequence for attaching the tubular section offabric 82 around the stent frame 80 includes providing longitudinalsuture markers (not shown) at 120° locations around the fabric to enableregistration with similarly circumferentially-spaced, commissurefeatures on the stent frame. After surrounding the stent frame 80 withthe fabric 82, a series of longitudinal sutures at each of the three120° locations secure the two components together. Furthermore, a seriesof stitches are provided along the undulating upper end 86 of the stentframe 80 to complete the fabric enclosure. In one embodiment, thetubular section of fabric 82 comprises polytetrafluoroethylene (PTFE)cloth, although other biocompatible fabrics may be used. Subsequently,the lower sealing flange 84 shown in FIG. 6 is attachedcircumferentially around a lower edge of the intermediate cloth-coveredframe 88.

FIG. 7A shows the valve member above the cloth-covered anchoring skirtand schematically shows one method of couple the two elements usingsutures. FIG. 7B illustrates the inner plastically-expandable stentframe 80 with cloth covering removed to indicate a preferred pattern ofcoupling sutures passed therethrough. The anchoring skirt 26 preferablyattaches to the sewing ring 62 during the manufacturing process in a waythat preserves the integrity of the ring and prevents reduction of thevalve's effective orifice area (EOA). Desirably, the anchoring skirt 26will be continuously sutured to the ring 62 in a manner that maintainsthe contours of the ring. In this regard, sutures may be passed throughapertures or eyelets 92 arrayed along the upper or first end 86 of theinner stent frame 80. Other connection solutions include prongs or hooksextending inward from the stent, ties, hook-and-loop fasteners (e.g.,Velcro® fasteners), snaps, adhesives, etc. Alternatively, the anchoringskirt 26 may be more rigidly connected to rigid components within theprosthetic valve member 24.

The construction steps described above in FIGS. 1-7 are relativelydetailed and time-consuming. Current hybrid valves such as describedabove take 11-12 hours total to build. This includes building a valvemember, as in FIGS. 1-3 , which takes approximately 7.5 hours, and thencovering the stent frame 80 with cloth and attaching it to the valvemember, which combined take another 3-4 hours of time. It wouldtherefore be desirable to reduce the labor hours to build such a valve.

Moreover, the aforementioned hybrid valve system does not haveexpandability during a valve-in-valve (ViV) procedure due to both therelatively rigid band subassembly 40 as well as the anchoring stentframe 80. Some attempts at making prosthetic valves expandable for ViVare known, but the resulting valve is expensive and difficult to build.Consequently, the present application discloses a number ofconfigurations of hybrid valves and methods of making that simplify theassembly and result in a ViV-adapted hybrid valve.

FIGS. 8A-8C illustrate a hybrid prosthetic heart valve 170 of thepresent application, which includes an upper valve member 172 coupled toa cloth-covered anchoring skirt 174. FIG. 8B shows the valve member 172in phantom to illustrate the contours of an expandable frame 176 of theanchoring skirt 174, and FIG. 8C is a perspective view of the entireheart valve 170 with portions at one commissure post 178 cutaway toreveal internal structural leaflet supports.

The valve member 172 of the hybrid prosthetic heart valve 170 sharessome structural aspects with the prior art valve member illustrated inFIG. 3 . In particular, there are three upstanding commissure posts 178alternating with three arcuate cusps 180 curving in an inflow direction.Three flexible leaflets 182 are supported by the commissure posts 178and cusps 180 and extend across a generally cylindrical flow orificedefined therewithin. The leaflets 182 are attached to an up and downundulating typically metallic wireform 184 via a cloth covering. As withearlier valve constructions, the upstanding posts 186 rise up adjacentto and just outside of the commissures of the wireform 184, and outertabs 188 of the leaflets 182 extend underneath the wireform, wrap aroundthe posts, and are secured thereto with sutures.

In the illustrated embodiment, the heart valve 170 also includes ahighly compliant sealing ring 190 extending outward therefrom atapproximately the interface between the valve member 172 and theanchoring skirt 174. The sealing ring 190 as well as the expandableframe 176 are covered with a fabric 192 that helps prevent leakagearound the outside of the valve once implanted. Furthermore, the sealingring 190 is also suture-permeable and may be used to secure the valve inplace in the native annulus.

FIGS. 9A-9C illustrate details of the exemplary expandable frame 176 foruse in the hybrid prosthetic heart valve 170 of FIGS. 8A-8C.

With specific reference to FIG. 9A, the lower frame 176 is shown inperspective and includes a plurality of circumferential row strutsconnected by a series of spaced axial column struts. Specifically, anupper or outflow row strut 200 extends continuously around a peripheryof the frame 176, and preferably follows a gently undulating path so asto match a similar shape of the underside of the upper valve member 172(FIG. 8B). As seen in FIG. 9A, three peaks 204 along the upper row strut200 correspond to the locations of the commissures 178 of the valve 170.In general, the lower frame 176 attaches to an inflow end of the uppervalve member 172, and preferably directly to or to fabric covering theinternal support frame. The lower frame 176 is initially generallytubular and expands to be somewhat conical with the free end farthestfrom the upper valve member 172 expanding outward but the end closestremaining the same diameter.

The upper row strut 200 includes a plurality of eyeholes 202 evenlyspaced apart and located just below the top edge thereof that are usefulfor securing the frame 176 to the fabric of the underside of the valvemember 172. A series of axial column struts 206 depend downward from theupper row strut 200, and specifically from each of the eyeholes 202, andconnect the upper row strut to two lower row struts 208. The lower rowstruts 208 circumscribe the frame 176 in zig-zag patterns, with aninverted “V” shape between each two adjacent column struts 206. Thelower row struts 208 preferably traverse horizontally around the frame,and the length of the column struts 206 thus varies with the undulatingupper row strut 200.

As mentioned above, the lower frame 176, in particular the inflow endthereof, may be plastically expanded, such as by balloon expansion, andmay be formed of a plastically expandable material, for example,stainless steel or cobalt-chromium (e.g., Elgiloy® alloy).Alternatively, the lower frame 176 may be self-expanding, such as beingformed from nitinol. In a conventional Edwards Intuity® valve, the upperrow strut 200 is generally ring-like without capacity for compression orexpansion. In the illustrated frame 176, on the other hand, a series ofspaced notches 210 are provided that permit expansion and contraction.That is, circumferential segments of the strut 250 are interrupted bythe V-shaped notches 210 that permits a limited amount of expansion,perhaps 3 mm in diameter, to accommodate a supplemental expandable valveto be inserted and expanded therein. More particularly, the upper rowstrut 200 (outflow end) of the frame 176 defines a nominal diameter seenin FIG. 9A that enables functioning of the valve member 172. The upperrow strut 200 is radially compressible from the nominal diameter to asmaller contracted diameter to enable compression of the outflow end ofthe frame 176 during delivery of the heart valve. The upper row strut200 is also radially expandable from the nominal diameter to a largerexpanded diameter upon application of an outward dilatory force fromwithin the stent frame such as in a valve-in-valve procedure.

It should be understood that the preferred embodiment of the hybridprosthetic heart valve 170 is configured for surgical delivery, whichdiffers from transcatheter or transapical delivery. In the latter cases,prosthetic heart valves are formed of structures and materials thatenable substantial compression of the valve into a relatively smalldiameter profile, to enable delivery through the vasculature (e.g.,transcatheter) or directly into the heart through an introducer (e.g.,transapical). The hybrid prosthetic heart valve 170, on the other hand,is typically delivered via open heart surgery or a less invasive versionthereof, such as through a mid-thoracotomy. “Surgical” delivery of heartvalves requires that the heart be stopped and the patient be placed oncardiopulmonary bypass, while transcatheter and transapical proceduresmay be done on a beating heart. Therefore, the hybrid prosthetic heartvalves 170 disclosed herein are only compressible to a limited degree,to enable a smaller delivery profile, but not totally compressible.

As shown in FIG. 9B, the modified frame 176 can be collapsed to apre-determined minimum diameter for delivery and expanded to apre-determined maximum diameter during a valve-in-valve procedure. Morespecifically, the upper row strut 200 of the illustrated frame 176 maybe collapsed by 2 mm relative to the nominal diameter for ease ofdelivery by compressing the V-shaped notches 210 as indicated. Becausethe notches 210 can only be compressed until the two corners meet, theframe 176 can only be collapsed by a predetermined amount. The exemplaryframe 176 is specifically designed to be collapsible to ease insertionthrough small incisions when the valve is implanted and for ease ofseating in the annulus. The amount of collapse could be as large asabout 40-50% by diameter, but would more preferably be about 2-3 mm, orbetween about 7-20% for heart valves having nominal operating diametersbetween about 19-29 mm. A compression of 2 mm in diameter, for example,corresponds to a change in circumference of about 6.28 mm. The stentframe is divided into 18 segments around its circumference by the axialcolumn struts 206. Therefore, by placing an initial gap of 0.35 mm (6.28mm/18) in each segment, the frame can collapse by 2 mm in diameterbefore adjacent segments make contact and hence prevent furthercompression.

FIG. 9C discloses that the upper row strut 200 of the illustrated frame176 may be subsequently expanded by up to 3 mm relative to a nominaldiameter during a valve-in-valve procedure. Because of the configurationof the upper row of struts, the outflow portion of the frame cannot beexpanded more than 3 mm. That is, the V-shaped notches 210 eventuallystraighten out, which prevents further expansion. Desirably, the frameis designed to expand 3 mm in diameter beyond its nominal diameter. Thenominal diameter is defined when the notches 210 are V-shaped, prior toeither contraction or expansion. Similar to the gaps for limitingcompression, the 3 mm in expansion corresponds to an about 9.42 mm (3mm×n) change in circumference. Therefore, each of the 18 segments limitsexpansion to 9.42 mm/18=about 0.52 mm. In this example, the length ofthe “V” shaped struts connecting each segment are thus 0.52 mm+0.35 mm(from the compression gaps)=0.87 mm During a valve-in-valve expansion,the expansion of the stent frame would be limited by theexpansion-limiting struts at the point where they became straight acrossthe gap between adjacent frame segments.

If it is not desired to have the frame collapsible but expansion isstill desired, the gaps could be reduced to the practical limit of lasercutting, for example, about 25 μm. With 18 gaps of 25 μm, the totalamount of compression would be (18×25 μm/n)=0.143 mm (about 0.006″).

In contrast, some earlier designs simply removed the upper row of strutsthat defines the outflow diameter of the frame. Such a frameconfiguration had no built-in way to limit the maximum expansion of thevalve during a valve-in-valve procedure. Additionally, there could be anadvantage to having hybrid valves that are collapsed by a limitedamount, for example, about 2-3 mm, for easier insertion. While a framewithout an upper row of struts could be collapsed, there is no built-inlimit the amount of compression. It might be desirable to have themaximum compression amount limited as disclosed herein for consistencyand for preventing physicians from trying to collapse the valve morethan it can safely be collapsed.

In addition, a number of valve-type indicators 212 are integrated intothe frame 176 at locations around its circumference, such as three valvesize indicators. In the illustrated embodiment, the valve sizeindicators 212 comprise small plate-like tags inscribed with thenumerical valve size in mm, for example 21 mm in the illustratedembodiment. The use of any alphanumeric characters and/or symbols thatsignify size or other feature of the valve are contemplated. The frame176 may be laser cut from a tubular blank, with the plate-like sizeindicators 212 left connected to one more of the struts. As shown, thesize indicators 212 are located just below the peaks 204 of theundulating upper row strut 200, connected between the correspondingeyehole 252 and the descending column strut 206. There are thus threesize indicators 212 spaced about 120° apart around the frame 176. Thislocation provides additional space between the upper row strut 200 andthe adjacent lower row strut 208. The inscribed or cutout valve sizenumerals are sufficiently large to be visualized with X-ray,Transesophageal Echocardiogram (TEE), or other imaging modality. In oneembodiment, the valve size numerals are from about 1.5 mm to about 2 mmin height, for example, about 1.75 mm in height.

FIG. 10A is an exploded perspective view of components of an alternativehybrid prosthetic heart valve 300. The alternative heart valve 300 doesaway with an internal stent or support frame previously shown as thecomposite bands 42, 48 in FIG. 1A, for example. The composite bandstructure was the primary source of circumferential rigidity to theheart valves in which they were employed, and thus an expansionstructure enabled valve-in-valve procedures. The alternative hybridheart valve 300 includes a lower compressible/expandable frame 302, asbefore, separate commissure posts 304 that are secured to the frame, andan undulating wireform 306 supporting flexible leaflets 308, also asbefore.

FIG. 10B shows a subassembly 310 including the wireform 306 juxtaposedwith the three leaflets 308, and an “integrated” subassembly 312 of theexpandable frame 302 with the commissure posts 304 attached thereto.Each of the flexible leaflets 308 has two tabs 309, and pairs of tabs onadjacent leaflets are shown projecting through (under) the invertedV-shaped commissures of the wireform 306. These pairs of tabs 309 thenwrap around one of the upstanding commissure posts 304 of thesubassembly 312, which are located adjacent to and radially outward fromthe wireform commissures. The subassemblies 310, 312 are eventuallycovered with biocompatible fabric such as polyester, and the pairs oftabs 309 and commissure posts 304 are secured to each other with a clothcovering (see FIG. 13 ).

Due to the attachment of the commissure posts 304 to the frame 302 thesubassembly 312 integrates the frame and commissure posts, while asdescribed below, an “integrated” frame may mean that the commissureposts are integrally formed of the same homogeneous material as the restof the stent frame. Integrated in this sense meaning the two componentsare securely attached together prior to assembly with thewireform/leaflet subassembly 310, either by securing the two parts orforming them at the same time from the same material. Furthermore, ahybrid heart valve with an “integrated” frame means that the frameprovides both the expandable skirt frame as well as commissure posts towhich the leaflets attach, without any additional structural bands, suchas the metal band 48 seen in FIG. 1A. With this configuration, thenumber of parts in the valve is reduced, which reduces assembly time andexpense.

FIGS. 10C and 10D illustrate a commissure post 304 from an outer and aninner perspective, respectively. A lower end of each of the commissureposts 304 includes a concave ledge 314 that matches the contour of oneof the peaks 316 in the undulating upper row of struts 318 of theexpandable frame. As seen in FIG. 10B, an outer plate 320 below each ofthe concave ledges 314 of the commissure posts 304 extends downward onthe outside of the expandable frame 302. Sutures 322 secure thecommissure posts 304 to the frame 302 via suture holes 324 that alignwith eyeholes 326 at the peaks 316 of the undulating upper row strut318. This shape matching followed by covering with fabric provides arelatively stable arrangement of the commissure posts 304 in theintegrated frame subassembly 312.

FIG. 11 is another exploded perspective view of subassemblies of thealternative hybrid prosthetic heart valve 300. In this view, thewireform in the subassembly 310 of the wireform and leaflets has beencovered with fabric, and features an outwardly projecting flap 330. Thefabric flap 330 is used to secure the wireform/leaflet subassembly 310to the subassembly 312 of the expandable frame 302 and commissure posts304. Furthermore, a suture-permeable sealing ring 332 may be attachedsuch as by sewing at the juxtaposition between the two subassemblies310, 312.

The relative positions of the wireform 306 and the frame/commissure postsubassembly 312 is seen in FIG. 12 , and also in further detail in FIGS.12A-12D, with the commissure posts 304 immediately outside of thecommissures of the wireform 306. Finally, FIG. 13 is a perspective viewof the finished hybrid prosthetic heart valve 300 entirely covered withfabric.

The removal of the aforementioned stent bands and attachment(integration) of the commissure posts 304 directly to the frame 302greatly simplifies construction, reduces labor hours, lowers the radialprofile of the valve by ˜1.6 mm, and allows for expansion during avalve-in-valve procedure. A preferred construction sequence involvesattaching the sealing ring 332 to the expandable frame 302, along withthree cloth-covered commissure posts 304, then attaching this assemblyto the wireform/leaflet subassembly 310 during final assembly.

The commissure posts 304 disclosed have specific features that interfacewith the frame 304 to add stability to the posts in all directions. Thatis, the specific surfaces 314, 320 that mate with the correspondingpeaks 316 on the frame 302 as well as the holes 324 that allow the poststo attach with sutures 322 to the frame provide excellent stability inall directions for subsequent covering with fabric. The commissure posts304 could be molded from polyester or some other biocompatible materialinto the shape shown here, or even produced using 3D printing.

A hybrid valve 340 built using the disclosed methods is shown in FIGS.14A and 14B with all but flexible leaflets 342 covered with cloth. Theimproved valve construction disclosed herein eliminates a separate stentsubassembly by combining the functions of that assembly (supporting theleaflets from underneath as well as from the sides in the commissurearea, and attachment of the sewing ring insert) with the stent frameassembly. As will be explained, the main components of the hybrid valve340 include a wireform 344 having alternating cusps and commissures thatsupports the leaflets 342, a lower expandable frame 346 integrated withcommissure posts 348, and preferably a sealing ring 350 around theperiphery of the cusps of the wireform 344. Several steps in theassembly process will now be described.

FIG. 15A shows the first step in the disclosed method of hybrid valveconstruction. A piece of PTFE tubular cloth 352 is first partiallyinverted and placed over the generally tubular stent frame 346 from thebottom, thus covering the inside, outside, and bottom of the frame.Subsequently, the cloth 352 is sewn to the frame 346 through frame holesand around a top circumferential row of struts 354 using an in-and-outstitch with double PTFE thread. FIG. 15B shows the cloth 352 pulled backon the inside and outside after sewing is complete, thereby exposing thetop of the stent frame 346. More particularly, the top circumferentialrow of struts 354 is left partly exposed; at least three peaksintermediate three valleys of the undulating row.

FIG. 16A shows the stent frame 346 covered in the cloth 352 and with asewing ring insert 356 placed adjacent the top row of struts 354. Thecloth layers below the sewing ring 356 have been rough cut, which isacceptable as they are subsequently covered in an outer layer of cloth,thus eliminating the need to “finish” the PTFE cloth in that area. Analternative method would be to fold those layers and finish them oneither the top or bottom of the sewing ring.

In FIG. 16B, the sewing ring insert 356 has been stitched to the top ofthe stent frame 346 in 6 locations to give it a desired scalloped shape.Six locations would be a minimum to define the high (commissures) andlow (cusp centers) points of its desired shape. It could be attached atmore locations to better define its shape. The PTFE cloth 352 from theinside of the stent frame 346 has been inverted over the sewing ringinsert 356 and formed by hand to follow the scalloped shape of theinsert. Subsequent to conforming the cloth to the insert as shown, boththe inner and outer layers of cloth are sewn together (between the stentframe and the insert).

After the sewing ring formation as shown in FIG. 16B, the next step isto cover three polymer (e.g. PET) commissure tip inserts 360, shown inFIG. 17 , with cloth 361, as shown in FIG. 18 . Because these inserts360 are simple 2D parts, they could potentially be sewn on a machine, or“socks” could be knitted to fit over them. Another option could be touse a different cloth, such as PET-based cloth, which could be laser cutand fused to make the covers for the inserts.

FIGS. 19A and 19B shows how the inserts 360 sit with respect to thestent frame 346 and outside of the commissures 362 of a wireform 364.The cloth is not shown in the sketch. The inserts 360 sit directly overthe peaks of the upper row of struts 354 of the stent frame 346. The tipinserts 360 and stent frame 346 could be sewn together through holes 366in the stent frame and a lower hole 368 in the inserts, through theirrespective layers of cloth. This provides a high degree of verticalstability to the commissures of the assembly. FIGS. 19A and 19B show twodifferent patterns for the holes 368 in the inserts 360, two or threetoward the lower end, while FIGS. 17 and 18 show a single hole. Ofcourse, other arrangements are contemplated.

After the cloth-covered commissure inserts 360 are attached to the stentframe/sewing ring assembly, final assembly would be performed. Finalassembly would include stitches from below the sewing ring insert 356(see FIG. 16A) through its hinge point, through the leaflets andwireform cloth, then down through all layers as an in-and-out stitch.

One method of creating commissure inserts uses a polyester (or othermaterial) tip piece 363, similar to that used in the Carpentier-EdwardsModel 2700 heart valve, as shown in FIG. 20 . The tip piece 363 wouldhave at least one hole 365 in the bottom to facilitate attachment to theexpandable stent frame after cloth covering, as well as other holes forsecuring the cloth, and securing the insert to the wireform cloth.

FIG. 21 shows an example of a PET tubular cloth 366, which could be usedto cover the component shown in FIG. 20 . The ends of the tube can beknitted closed, as is done on prior art annuloplasty rings, or fusedclosed with ultrasonic, laser, or heat methods. With one end closed, thepiece 364 from FIG. 20 can be inserted from an open end. The cloth 366can then be folded over to form multiple layers on one side tip piecefor subsequent leaflet attachment.

FIGS. 22A and 22B show a commissure insert 368 made in the fashionattached to a cloth-covered expandable stent frame described above.Three such commissure inserts would be attached to the cloth-coveredstent frame, which would then be ready for final assembly with thewireform-leaflet assembly. A second method of making commissure insertsuses a non-woven fabric such as Reemay® spunbonded polyester.

FIG. 23 shows solid fabric inserts 370 made in this manner. The inserts370 can simply be die (or laser, etc.) cut from non-woven fabric sheetof the desired thickness and porosity. These inserts 370 would beimmediately ready to attach to the cloth-covered stent frame 372 asshown in FIG. 24 . As an alternative to making them from a homogenoussheet, they could be made from a composite that had, for example, a verydense and stiff layer that could face the inside of the valve to addsupport and minimize leakage, and a less dense layer on the outside thatwould be easy to stitch to during final valve assembly. For even morestiffness, the composite could contain a layer of polyester sheet,either inserted into a pocket cut into a single, thick section offabric, or as a layer in a composite structure.

FIGS. 25-31 illustrate alternative integrated anchoring skirt andcommissure post subassemblies. As described above with respect to FIGS.10-13 , the subassembly 312 shown in FIG. 10B eliminates the need forannular structural bands, which bands provide stability and rigidity butwhich impede the ability of the valve to expand post-implant. Each ofthe alternative subassemblies shown in FIGS. 25-31 also eliminate theneed for the structural bands, and further integrate the anchoring skirtand the commissure posts.

FIG. 25A shows a still further assembly 400 of the structural componentsof a hybrid prosthetic heart valve having an integrated frame member 402much like those described above but formed of a single piece. Aschematic wireform 404 is shown situated on top of the frame member 402in FIG. 25A, with flexible leaflets and a cloth cover not shown andrepresenting a wireform/leaflet subassembly such as shown at 310 in FIG.11 . The schematic wireform 404 is shown with an outwardly extendingsewing flange 406, which may be formed by joined lengths of two fabrictabs that wrap around and cover the wireform. When covered with cloth,the frame member 402 serves as the supportive component for thewireform, leaflets and sealing ring. Further, when covered with cloth,the frame member 402 provides an effective seal against paravalvularleaking (PVL) and circumferential stability to the valve.

The integrated frame member 402, which is also shown in FIGS. 25B-25D,comprises a lower expandable skirt portion 410, an upper annulus band412, and leaflet support posts 414. The skirt portion 410 comprises anumber of chevron patterned or V-shaped struts that can be easilycrimped and then expanded. The annulus band 412 provides real estate forthe attachment of a sealing ring (not shown), and preferably includes aseries of holes around its circumference through which to pass suturesconnecting the sealing ring. The integrated frame member 402 includesmultiple cuts that enable post-implant expansion and may be laser-cutfrom a suitable metal such as Elgiloy and electro-polished.

The frame member 402 is desirably formed from a tubular blank of asuitable material, and has a generally circular inflow or lower edge andan undulating outflow or upper edge. More particularly, the upper edgedefines three arcuate cusp portions 416 intermediate three upstandingcommissure posts 418. The undulating upper edge is shaped to closely fitunderneath the wireform 406. After assembling the frame member 402 withthe rest of the heart valve components, the skirt portion 410 istypically crimped in a generally conical manner such that its lower edgehas a smaller diameter than its upper edge.

Compression/expansion sections 420 along the annulus band 412 are alsoadded to enable a limited collapse of the frame member 402 duringdelivery. The compression/expansion sections 420 comprise slits formedin the upper edge of the frame member 402 that have spaces enabling alimited compression, and also permit expansion. In a preferredembodiment, solid segments 422 spaced around the annulus band 412 areconnected by thin inverted U-shaped bridges 424.

As seen in FIG. 25D, the frame member 402 further includes a number ofslits in the region of the commissures 418 to facilitate expansion ingeneral flexibility of the frame member. An elongated central slit 426extends nearly the entire height of each of the commissures 418. Regionsof expandable circumferential struts 428 are positioned within the skirtportion 410 axially aligned with both the compression/expansion sections420 and the central slits 426. When an outward radial force is appliedfrom within the heart valve having the frame member 402, the annulusband 412 permits expansion because of both the sections 420 and slits426. Additionally, short arcuate slits 430 are formed at the base ofeach of the commissure posts 418, generally following a truncatedundulating line joining the cusp portions 416. These slits 430 reducethe radial stiffness of the posts 418 such that most of thephysiological load absorbed by the flexible leaflets is transferred tothe wireform 406, rather than to the posts.

Despite the arcuate slits 430 in the frame member 402 of FIGS. 25A-25D,there are concerns that such an integrated frame design will stiffen thewireform commissure post area, thus altering the load carry mechanism ofproven valve platforms. To alleviate such concerns, the three commissureposts may be made of three separate pieces, preferably using polymericmaterial, such that when connected with the underlining metal frame withsutures, there will not be metal to metal contact.

For instance, FIGS. 26A-26D illustrate an alternative frame member 440that is configured about the same as the frame member 402, but hasseparate commissure posts 442. The frame member 440 is shown situatedjust below a wireform assembly 441 in FIG. 26A. As seen in FIGS.26C-26D, the annulus band region 444 and the in-flow strut region 446are exactly same as that of the frame member 402. The only difference isseparate commissure posts 442 preferably made of plastic material thatwill be sewn together with the frame member 440 using sutures 448 beforebeing covered with cloth. A pair of attachment holes 450 is desirablyformed in each of the commissure posts 442 for this purpose. As before,the crimpable and expandable frame member 440 without commissure postsis laser-cut and electropolished.

Although the ability to compress and expand the frame members may be anadvantage, the present application also contemplates integrated framemembers for a hybrid prosthetic heart valves that are not eitherexpandable or compressible. FIGS. 27A-27B show an assembly 460 of thestructural components of a hybrid prosthetic heart valve including anintegrated frame member 462 with a lower expandable skirt portion 464,an upper annulus band 466, and leaflet support posts 468. The annulusband 466 provides real estate for the attachment of a sealing ring (notshown). As before, the integrated frame member 462 may be laser-cut froma suitable metal tube such as Elgiloy and electro-polished. A wireform470, such as in the subassembly 310 in FIG. 11 , is illustrated justabove the undulating upper end of the frame member 462, with flexibleleaflets and a cloth cover not shown for clarity.

As seen best in FIG. 27B, the frame member 462 has an outflow or upperedge 472 without capacity for either compression or expansion. That is,a plurality of solid segments 474 spaced around the annulus band 462 areconnected by small solid bridges 476. Each of the solid segments 474preferably has a through hole 478 for use in an attaching a sewing ringaround the periphery thereof.

FIG. 28A shows another assembly 480 of the structural components of aprosthetic heart valve including a non-compressible, non-expandableintegrated frame member 482 much like the one in FIGS. 27A-27B, but withseparated commissure posts 484. Several suture holes 486 in thecommissure posts are also added to help secure the commissure posts 484to an annulus band 488 of the frame member 482, much like is shown inFIG. 26A.

FIG. 25A is a fully integrated frame member 402, with concerns overstiffened commissure posts. The frame member 442 shown in FIG. 26Aalleviated that concern with three separate commissure posts 442, butthose require sewing together with the expandable frame, which increasesthe time and steps when assembling the valve. In order to preserve thesame load bearing characteristics of the existing commercial valveplatforms, while still having a relative easy valve assembly procedure,the embodiments shown in FIGS. 29 and 31 are also contemplated.

FIG. 29 shows an assembly 500 that includes an expandable frame 502 muchlike the frame 176 described above with respect to FIG. 9A. The frame502 is secured via sutures to a stent band 504 with upstandingcommissures 506 to form an integrated frame member. This stent band 504is essentially the inner band 95 from FIG. 1A, with suture holes 505around its circumference to enable secure attachment to the top row ofstruts of the frame 502. An upper row of struts 508 includes regularlyspaced compressible/expandable segments 510 to enable pre-implantcompression, and post-implant expansion during a valve-in-valveprocedure.

The assembly 500 is again crimpable and expandable. The stent band 504is formed of a polymer (e.g., polyester) material that is breakable whenin expansion force is applied within the valve. This makes the wholevalve expandable for valve-in-valve applicable. Because of the polymercommissures 506, the valve load carrying characteristics will be exactlythe same as the existing commercial valve platform, thus hydrodynamicperformance and durability of the valve shall be the same as theexisting commercial valve as well. The relative position of thepolyester band and the expandable frame can be assembled as illustratedin FIG. 29 , with the stent band 504 positioned immediately above theframe member 502. Conversely, as seen in FIG. 31 , the stent band 504may be located partly radially within the frame 502, in an overlappingmanner. This aligns the series of through holes 505 in the stent band504 with eyeholes 512 provided in the frame 502, which greatlyfacilitates assembly, thus reducing time and expense.

Some Improvements Over Existing Designs:

1. Integrate the metal stiffener band, the stent frame and/or thepolyester band together.

2. The commissure posts, the sewing ring section, as well as the chevronpatterned strut section are expandable such that they expand uniformlywithout distorting the wireform.

3. Reduce the radial stiffness compared with the current heart valveframes so that a transcatheter valve balloon/frame can push the newvalve open at least about 2 mm.

4. Integrated commissure posts for holding the leaflet tabs imposereduced or minimal forces on the leaflet, with most of the forcestransferred to the wireform

5. No leakage path through the commissure post areas or the sewing ringattachment area.

6. Ease of locating and sewing/clipping/inserting the sewing ring on theframe.

7. During the crimping, expansion, and other manufacturing steps, theframe does not buckle/remains stable, especially at the commissureposts.

8. Crimpability at the annulus region reduces the profile of the valveduring valve insertion.

Some Advantages:

1. Expandable hybrid prosthetic heart valves permit valve-in-valveprocedures, improving valve performance.

2. Integrated design simplifies assembly, reducing labor and materialcosts.

3. Crimping the valve reduces its profile, which improves visibilityduring valve insertion and deployment, enhancing the user's experience.

While the disclosure references particular embodiments, it willunderstood that various changes and additional variations may be madeand equivalents may be substituted for elements thereof withoutdeparting from the scope or the inventive concept thereof. In addition,many modifications may be made to adapt a particular situation or deviceto the teachings herein without departing from the essential scopethereof. Therefore, it is intended that the disclosure not be limited tothe particular embodiments disclosed herein, but includes allembodiments falling within the scope of the appended claims.

What is claimed is:
 1. A hybrid prosthetic heart valve having an inflowend and an outflow end, comprising: a valve member including afabric-covered undulating wireform with alternating cusps andcommissures supporting a plurality of flexible leaflets configured toregulate one-way blood flow therethrough, the valve member having noadditional structural bands; and a fabric-covered expandable inflowstent frame having a radially-expandable inflow end and an outflow endthat undulates with peaks and valleys corresponding to an inflow end ofthe wireform, the stent frame being attached to and projecting in aninflow direction from an inflow end of the wireform; and a plurality ofseparate commissure posts connected to the outflow end of the stentframe and projecting axially therefrom so as to be located radiallyoutward from the wireform commissures, wherein the flexible leafletspass radially outward through the wireform commissures and attach to thecommissure posts, wherein the commissure posts are secured directly ontop of and in alignment with the stent frame outflow end, eachcommissure post having a contoured lower ledge that matches a contour ofone of the peaks in the undulating outflow end of the stent frame. 2.The prosthetic heart valve of claim 1, and wherein the stent frameoutflow end permits post-implant expansion from a first diameter to anexpanded diameter larger than the first diameter upon application of anoutward dilatory force from within the outflow end substantially largerthan forces associated with normal physiological use.
 3. The prostheticheart valve of claim 2, wherein the stent frame outflow end isconfigured to be compressed to a constricted diameter smaller than thefirst diameter.
 4. The prosthetic heart valve of claim 1, wherein thestent frame outflow end is non-compressible and non-expandable.
 5. Theprosthetic heart valve of claim 1, wherein the commissure posts aresecured with sutures to the stent frame outflow end.
 6. The prostheticheart valve of claim 1, wherein the commissure posts each includes aportion that extends down below and to the outside of the inflow end ofthe stent frame and has a through hole which aligns with an eyehole inthe stent frame and the commissure post is secured to the stent framewith a suture through the aligned through hole and eyehole.
 7. Theprosthetic heart valve of claim 1, wherein the commissure posts areformed of a polymer insert covered with fabric.
 8. The prosthetic heartvalve of claim 1, wherein the commissure posts are formed of a non-wovenfabric.
 9. The prosthetic heart valve of claim 1, further including asuture-permeable sealing ring enclosed by a portion of the fabriccovering the stent frame and extending around a periphery of the outflowend of the stent frame.
 10. A hybrid prosthetic heart valve having aninflow end and an outflow end, comprising: a valve member including afabric-covered undulating wireform with alternating cusps andcommissures supporting a plurality of flexible leaflets configured toregulate one-way blood flow therethrough, the valve member having noadditional structural bands; a generally tubular fabric-coveredexpandable inflow stent frame having a radially-expandable inflow endand an outflow end that undulates with peaks and valleys correspondingto an inflow end of the wireform, the outflow end being secured to andprojecting from the inflow end of the valve member, wherein the outflowend of the stent frame includes a circumferential structure defining afirst diameter that enables physiological functioning of the valvemember when implanted, the circumferential structure being radiallyexpandable from the first diameter to a larger expanded diameter uponapplication of an outward dilatory force from within the stent framesubstantially larger than forces associated with normal physiologicaluse, wherein the circumferential structure has limited radiallycompressibility of between about 7-20% of the first diameter to reducethe size of the outflow end during delivery of the heart valve; and asuture-permeable sealing ring enclosed by a portion of the fabriccovering the stent frame and extending around a periphery of the outflowend of the stent frame.
 11. The prosthetic heart valve of claim 10,wherein the stent frame includes a plurality of circumferential rowstruts connected by a series of spaced axial column struts, and thecircumferential structure is an outflow row strut that extendscontinuously around a periphery of the stent frame having peaks andvalleys, and the outflow row strut has a series of spaced V-shapednotches that permit limited expansion and contraction.
 12. Theprosthetic heart valve of claim 10, further including a plurality ofseparate commissure posts connected to the outflow end of the stentframe and projecting axially therefrom so as to be located radiallyoutward from the wireform commissures, wherein the flexible leafletspass radially outward through the wireform commissures and attach to thecommissure posts.
 13. The prosthetic heart valve of claim 12, whereinthe commissure posts are secured with sutures to the stent frame outflowend.
 14. The prosthetic heart valve of claim 13, wherein the commissureposts are secured directly on top of and in alignment with the stentframe outflow end, each commissure post having a contoured lower ledgethat matches a contour of one of the peaks in the undulating outflow endof the stent frame.
 15. The prosthetic heart valve of claim 14, whereinthe commissure posts each includes a portion that extends down below andto the outside of the inflow end of the stent frame and has a throughhole which aligns with an eyehole in the stent frame and the commissurepost is secured to the stent frame with a suture through the alignedthrough hole and eyehole.
 16. The prosthetic heart valve of claim 12,wherein the commissure posts are formed of a polymer insert covered withfabric.
 17. The prosthetic heart valve of claim 12, wherein thecommissure posts are formed of a non-woven fabric.
 18. The prostheticheart valve of claim 10, wherein the sealing ring is formed of siliconeinner core.
 19. A hybrid prosthetic heart valve having an inflow end andan outflow end, comprising: a valve member including a fabric-coveredundulating wireform with alternating cusps and commissures supporting aplurality of flexible leaflets configured to regulate one-way blood flowtherethrough, the valve member having no additional structural bands; agenerally tubular fabric-covered expandable inflow stent frame having aradially-expandable inflow end and an outflow end that undulates withpeaks and valleys corresponding to an inflow end of the wireform, theoutflow end being secured to and projecting from the inflow end of thevalve member; a suture-permeable sealing ring enclosed by a portion ofthe fabric covering the stent frame and extending around a periphery ofthe outflow end of the stent frame; and a plurality of separatecommissure posts connected to the outflow end of the stent frame andprojecting axially therefrom so as to be located radially outward fromthe wireform commissures, wherein the flexible leaflets pass radiallyoutward through the wireform commissures and attach to the commissureposts, wherein the commissure posts are secured with sutures to thestent frame outflow end.
 20. A hybrid prosthetic heart valve having aninflow end and an outflow end, comprising: a valve member including afabric-covered undulating wireform with alternating cusps andcommissures supporting a plurality of flexible leaflets configured toregulate one-way blood flow therethrough, the valve member having noadditional structural bands; a generally tubular fabric-coveredexpandable inflow stent frame having a radially-expandable inflow endand an outflow end that undulates with peaks and valleys correspondingto an inflow end of the wireform, the outflow end being secured to andprojecting from the inflow end of the valve member; a suture-permeablesealing ring enclosed by a portion of the fabric covering the stentframe and extending around a periphery of the outflow end of the stentframe; and a plurality of separate commissure posts connected to theoutflow end of the stent frame and projecting axially therefrom so as tobe located radially outward from the wireform commissures, wherein theflexible leaflets pass radially outward through the wireform commissuresand attach to the commissure posts, wherein the commissure posts areformed of a non-woven fabric.
 21. A hybrid prosthetic heart valve havingan inflow end and an outflow end, comprising: a valve member including afabric-covered undulating wireform with alternating cusps andcommissures supporting a plurality of flexible leaflets configured toregulate one-way blood flow therethrough, the valve member having noadditional structural bands; and a fabric-covered expandable inflowstent frame having a radially-expandable inflow end and an outflow endthat undulates with peaks and valleys corresponding to an inflow end ofthe wireform, the stent frame being attached to and projecting in aninflow direction from an inflow end of the wireform, wherein the stentframe outflow end is non-compressible and non-expandable; and aplurality of separate commissure posts connected to the outflow end ofthe stent frame and projecting axially therefrom so as to be locatedradially outward from the wireform commissures, wherein the flexibleleaflets pass radially outward through the wireform commissures andattach to the commissure posts.
 22. A hybrid prosthetic heart valvehaving an inflow end and an outflow end, comprising: a valve memberincluding a fabric-covered undulating wireform with alternating cuspsand commissures supporting a plurality of flexible leaflets configuredto regulate one-way blood flow therethrough, the valve member having noadditional structural bands; and a fabric-covered expandable inflowstent frame having a radially-expandable inflow end and an outflow endthat undulates with peaks and valleys corresponding to an inflow end ofthe wireform, the stent frame being attached to and projecting in aninflow direction from an inflow end of the wireform; and a plurality ofseparate commissure posts connected to the outflow end of the stentframe and projecting axially therefrom so as to be located radiallyoutward from the wireform commissures, wherein the flexible leafletspass radially outward through the wireform commissures and attach to thecommissure posts, wherein the commissure posts are formed of a non-wovenfabric.